Connectionists: New paper: modeling neuron-astrocyte interactions

[Renaud Jolivet]

Dear colleagues,

I would like to draw your attention to a paper we recently published 
modeling the exchange of metabolites between neuron and astrocytes and 
providing a new method for evaluating the brain's energy budget. The 
paper is available at 
http://frontiersin.org/neuroenergetics/paper/10.3389/neuro.14/004.2009/

Jolivet R, Magistretti PJ, Weber B.
Deciphering neuron-glia compartmentalization in cortical energy metabolism.
Front. Neuroenerg. 1:4. doi:10.3389/neuro.14.004.2009

Energy demand is an important constraint on neural signaling. Several 
methods have been proposed to assess the energy budget of the brain 
based on a bottom-up approach in which the energy demand of individual 
biophysical processes are first estimated independently and then summed 
up to compute the brain's total energy budget. In this paper, we address 
this question using a novel approach that makes use of published 
datasets that reported average cerebral glucose and oxygen utilization 
in humans and rodents during different activation states. Our approach 
allows us [1] to decipher neuron-glia compartmentalization in energy 
metabolism and [2] to compute a precise state-dependent energy budget 
for the brain. Our results suggest that glycolysis occurs for a 
significant part in astrocytes whereas most of the oxygen is utilized in 
neurons. As a consequence, a transfer of glucose-derived metabolites 
from glial cells to neurons has to take place. Furthermore, we find that 
the amplitude of this transfer is correlated to the activity level of 
the brain and to the oxidative activity in astrocytes. Our method allows 
for a straightforward assessment of the brain's energy budget from 
macroscopic measurements with minimal underlying assumptions.

Best regards,
Renaud Jolivet

-- 
Dr Renaud Jolivet
Roche Research Fellow
University of Zurich
Institute of Pharmacology & Toxicology

University Hospital Zürich
Nuclear Medicine
Rämistrasse 100
CH-8091 Zürich

Tel: +41 76 437 9798

rjolivet at pharma.uzh.ch
http://www.pharma.uzh.ch/research/functionalimaging/members/jolivet.html